Would you like to inspect the original subtitles? These are the user uploaded subtitles that are being translated: 1 00:00:00,480 --> 00:00:03,930 DNS or domain name system service 2 00:00:07,620 --> 00:00:12,870 so on our previous lessons of course we mentioned the IP which is the Internet Protocol. 3 00:00:12,870 --> 00:00:21,510 So a computer must have an IP to communicate over network so if it cannot receive an IP it cannot exchange 4 00:00:21,510 --> 00:00:24,490 data over the network. 5 00:00:24,510 --> 00:00:32,460 So you know that in order to communicate with one computer another computer will need to know the IP 6 00:00:32,460 --> 00:00:35,190 address of the computers that it wants to communicate with. 7 00:00:36,800 --> 00:00:44,690 It's gonna be difficult for all computers that will be contacted to remember a numerical IP address 8 00:00:44,690 --> 00:00:53,470 value therefore the DNS or domain name system protocol has emerged the DNS protocol matches computer 9 00:00:53,470 --> 00:00:55,420 threads to their names. 10 00:00:55,570 --> 00:00:59,170 So it makes Name IP matching possible. 11 00:00:59,410 --> 00:01:04,170 This way we can only access a site that we know the name of. 12 00:01:04,190 --> 00:01:12,490 Now there are servers that provide a DNS service and these are called DNS servers so the DNS protocol 13 00:01:12,550 --> 00:01:22,460 uses the UDP DCP port 53 and it computer automatically receives a DNS server address when it receives 14 00:01:22,460 --> 00:01:32,120 an IP however we can also manually define this address so if we want to communicate with a computer 15 00:01:32,120 --> 00:01:38,570 without a defined DNS over the network we're going to need to know the IP address of each computer or 16 00:01:38,570 --> 00:01:40,820 web address that we want to reach. 17 00:01:40,820 --> 00:01:49,980 Otherwise communication is going to take place so the DNS protocol works on our computer as follows. 18 00:01:51,890 --> 00:01:56,260 Let's suppose that we want to access dub dub dub dub Google dot com. 19 00:01:56,290 --> 00:01:57,350 Who would ever want to do that. 20 00:01:58,390 --> 00:02:06,520 Anyway when we type it into our web browser and click on enter the web browser forwards the request 21 00:02:06,520 --> 00:02:12,790 to the network card and network card then receives a request and forwards a request to the DNS server 22 00:02:13,210 --> 00:02:20,320 defined in the IP setting and the DNS server transmits the IP information from dub dub dub Google dot 23 00:02:20,320 --> 00:02:27,190 com to the requesting computer and the computer receives a request to the network layer and transmits 24 00:02:27,190 --> 00:02:28,120 it to the web browser. 25 00:02:29,550 --> 00:02:36,520 And the web browser shows us our request so different commands are used on Linux and Windows computers 26 00:02:36,520 --> 00:02:41,790 to view DNS setting to view it on Windows computer. 27 00:02:43,350 --> 00:02:49,620 Run run is written in command IP config. 28 00:02:49,800 --> 00:02:57,170 All is entered on the incoming screen and then the address that you see here is a DNS server address. 29 00:02:59,200 --> 00:03:00,010 Linux 30 00:03:04,040 --> 00:03:13,940 is a bit different open up terminal type leaf pad slash ATC slash resolved dot conf at the end of the 31 00:03:13,940 --> 00:03:22,160 command prompt enter the DNS server address of the next computer computers displayed on the screen and 32 00:03:22,160 --> 00:03:29,910 map and scanning so when we scan with then map it attempts to resolve the DNS name of each IP address 33 00:03:29,910 --> 00:03:38,550 it scans by default so for this purpose it performs an IP name analysis on the DNS server for each IP 34 00:03:38,550 --> 00:03:39,470 address. 35 00:03:39,470 --> 00:03:46,910 So in this case depending on the DNS server name IP analysis may take a little time and this increases 36 00:03:46,910 --> 00:03:48,800 the scanning time of course. 37 00:03:49,010 --> 00:04:00,200 So to prevent this when we scan with an parrot and map scans without DNS resolution and map our scanning 38 00:04:01,490 --> 00:04:06,430 so when we scan within map the names of the target servers can always give us some clues. 39 00:04:07,490 --> 00:04:11,990 So I means in this case the IP name analysis is required for this. 40 00:04:11,990 --> 00:04:19,040 We'll use the r parameter and then this parameter requires DNS resolution for each IP address. 4690